bickford



(No Model.)

' J. O. BIOKPORD.

MANUFACTURE OF INDIA RUBBER BOOTS AND SHOES. No. 308,736. v PatentedDec. 2, 1884.

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JOHN c. BIGKFORD, or

PATENT OFF CE,

BRISTOL, RHODE' ISLAND.

MANUFACTURE OF INDIA- RUBBER BOOTS AND SHOES.

SPECIFICATION forming part of Letters Patent No. 308,786, dated December2, 1884.

Application filed May 6, 1884. (N0 model.)

To all whom it may concern: Be it known that I, JOHN C. BIOKFORD, 0Bristol, in the county of Bristol and State of Rhode Island, haveinvented an Improvement in the Manufacture of India-Rubber Boots andShoes, of which the following is a specification. I

Heretofore in the manufacture of rubber bootsand shoes the heels and thethick soles have. been first cemented to the bottom of the boot or shoeand then placed in the oven for open vulcanization without molding orcompression, and as a result ofthis process the attachment of the heelor-sole to the adjoining parts of the boot or shoe has been imperfectlyeffected, and in ordinary wear the heels and soles are liable to becomeloosened and to separate from the bottom of the boot or shoe;

- and the object of my improvement is'to secure the heel and sole to thebottom of the boot or shoe in a permanent manner; and to this end Iattach the heel or sole to the adjoining parts by cement, and thenvulcanize an elevation of the bootplaced upon the boottree preparatoryto vulcanization, and showing a spring device adapted to secure properlocal pressure upon the heel during the pro cess of vulcanization. Figs.3 and 4 are perspective views of the spring device employed to securelocal pressure upon the heel and the heel and sole. elevation of the caremployed in the vulcanizing-oven, and shows an arrangement of springsadapted to secure the required pressure upon the heel in process ofvulcanization.

In the accompanying drawings, Fig. 1 represents a vertical section ofthe lower portion of a rubber bootin which the previouslymolded heel Aand the sole-piece B are cemented to the bottom piece, D, of the bootprevious to vulcanization, and in carrying out my improved process forattaching the Fig. 5 represents a side heels or soles to rubber bootsand shoes I preferably provide a spring device as shown in Fig. 3,consisting of the plate a, whichis springs c c, and after the heel A hasbeen placed in position upon the boot the plate a is to be placed overthe bottomof the same, and the cross bar 12 brought over the projectingend of the boottree d, as shown in Fig. 2, causing the requiredextension of the springs c c to produce the proper degree of' pressureupon the heel, and when so prepared the boots may be suspended in thevulcanizing-oven by means of the ring or eye 6 at the upper end of theboot-tree. Whenever it is desired to secure both the heel and sole inthis manner, a spring device, as shown in Fig. 4, may be used, the platea being in this case extended so as to embrace the sole with the heel. p

A modification of the device for securing the vulcanization of theboot,with local press- "ure upon the heel, as arranged in a vuloanizing-car, is shown in Fig 5, in which the boot tree dis placed bottom upupon the pin f, projecting upward from the bar 9, the heel A being heldunder pressure by means of the spring 0, to the outer end of which thepressure plate a is attached. when thus filled with boots, is to beplaced in the vulcanizing-oven, and in the process of vulcanization theboot-heel thus held under pressure will become firmly attached to theother parts of the boot, and willnot thereafter be liable to looseningand separation, as heretofore.

I am aware that it is common to inclose articles of rubber in molds forthe purpose of vulcanization, in which process the cemented parts willbecome firmly attached to each other under pressure; but in all suchinstances the whole extent of the article manufactured has been includedin the cavity of the mold,

ever been applied in the process of open vulcanization, as in themanufacture of boots and shoes.

I claim as my invention- The method of attaching the heel, or heelconnected to the cross-piece b by means of the The car vE,

and I am not aware that local pressure has and sole, to rubber boots orshoes, which distended by the boot tree or last when uneonsists in firstcementing the heel, or heel dergoing the process of vulcanization,suhand sole, to the adjoining parts, which are stm'itially as described.

held upon a boot tree or last, with the suh- JOHN G. BIOKFORD. 5 sequentapplication of direct exterior press- W'itnesses:

me upon the heel, or heel and sole, while the J AMES \V. XVILLIAMs,

upper portion of the boot or shoe is openly SOORATES SCHOLFIELD.

